DEPARTMENT OF COMMERCE 

BUREAU OF FISHERIES 

HUGH M. SMITH, Commissioner 



DANGER TO 
TAR 



ERIES FROM OIL AND 
OF WATERS 



By J. S. OUTSELL 

Scientific Assistant, U. S. Bureau of Fisheries 



Appendix Vll to the Report of the U. S. Commissioner 
OF Fisheries for 1921 




Bureau of Fisheries Document No. 910 



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1921 



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L.IBRAHY OF CONaNESS I 



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DANGER TO FISHERIES FROM OIL AND TAR POLLUTION 

OF WATERS.' 



J5y J. S. Outsell, 
Seientijic As.si.^Uivt, U. S. Bureau of Fisheries. 



Recently the casting of oil on already sorely troubled waters has 
increased at such a rate, has been accused as the source of so many 
ills of fishermen and shell fishermen and even of ornithologists, and 
has become such an obvious nuisance, that a considerable realization 
of the extent of the contamination and a sense of the possible evil 
effects have been aroused. So great is the discharge of oils of various 
sorts that in this country it has been proposed to skim oft' the oil 
from some harbor waters and make it available by proper treatment. 
In Switzerland a patent has been taken out for the recovery of oils 
from backwaters. It is very deshable, therefore, to present a brief 
review of the information available regarding the extent and nature 
of oil and oil-like pollutions with consideration of the possibilities 
of danger therefrom. 

SOURCES OF POLLUTION. 

Danger of fatal contamination from the poisonous substances seems 
to lie chiefly in the gas plants and petroleum distilleries, which on one 
occasion or another, if not regularfy, find it convenient to let certain 
products drain into the nearest body of water; in tankers and oil- 
engined craft, which are able to use tar, tar oils, and a great variety 
of petroleum distillates; in oil-burning steamships; and in the wash- 
ings of oils and tars from roads. 

Gas houses and oil refineries are located on all sorts of bodies of 
water larger than brooks. In smaller streams, and particularly in 
those inhabited by salmonids, discharges are doubtless frequently 
fatal to fish life and quite ruinous to the fish value of the water. In 
larger bodies the actual destruction of fish is apt to be small or incident 
to exceptional discharges, and the chief harm probably will come 
from the uninhabitability of the water, especially if this means the 
rendering unfit of a spawning ground or the forming of a barrier 
thereto as for salmon or shad. 

In streams large enough for steamers, and in all larger bodies of 
water, there are added to the contributions from gas houses and 
refineries those from tankers and other ships, and the dangers to 
fishes from poisoning or coating of gills are correspondingly increased. 
These larger navigable bodies may be spawning grounds and are 
almost sure to be gateways to what should be spawning grounds. 
The danger here, therefore, of keeping fish away from the spawning 



» Appendix VII to the Report of the U. S. Commissioner of Fisheries for 1921. B. F. Doc. 910. 

3 



4 r. S. BUREAU OF FISHKlllF.S. 

grounds is far <ireater than the (hmgcr of destruction. It has been 
charged, but apparently not specifically estabhshed, that fish in har- 
bors and the lower stretches of rivers have been killed by the dump- 
ing of oil from tankers. All of these vessels must clean out their 
tanks before they refill them and ai-e prone to do so in harbor or as 
near there as may be. 

Well out at sea and in the larger l)ays the only source of consider- 
able oil pollution seems to lie in the shipping, which, if it can not 
discharge in or near har})ors, will do so at sea. Moreover, it seems 
clearly established that great oil films do form at sea. Huge patches 
have frequently been observed, and Collinge reports that sea birds 
have been found dead and dying by hundreds off the English coast, 
their feathers saturated witli oil. Death of sea birds from the same 
cause is reported from our Pacific coast. 

Tar from freshly tarred roads may be washed bodily into gutters 
and thence into streams or other bodies of water. Apparently, how- 
even-, the greatest danger of direct action from tarred roads is from the 
fact that under the various influences at work — presumably heat, the 
mechanical action of vehicles, and soluble action of oils — -poisonous 
substances are yielded to road washings for a great length of time. 
Various people in England, as recorded especially in the (London) 
Fishing (jrazett(% have described instances or experiments which indi- 
cate tbe continued poisonous action of tarred roads. Richmond 
found that although an undisturbed tarred surface became innocuous 
in three weeks, washings from material chipped from a road which 
had not been tarred for approximately one year were fatal to fish. 
Tarred road washings appear to be noticeably destructive of fish and, 
largely through the destruction of food organisms, of fisheries, chiefly 
in streams not larger than small rivers and ponds, particularly trout 
waters. In well-developed country so fortunate as to possess salmon 
streams, tarred roads doubtless constitute a menace to the salmon 
fishery. 

Oil from motor cars, etc., goes into small as well as large bodies of 
water and is of greatest volume at large towns. 

EFFECTS OF OIL POLLUTION. 

Oil remains in part as a surface film on the water, and is probably 
in part emulsified and distributed in intermediate strata, while the 
heavier fractions are deposited on the bottom, where they persist 
for a long time. All parts are washed ashore to be deposited on the 
beaches and vegetation between tide marks. 

This pollution may affect the fisheries in various ways: By actu- 
ally Icilling or repelling the fish when they approach the shores in 
their migrations, at the only time when they can be caught; by sick- 
ening or killing bottom-dwelling species such as oysters; by killing 
floating eggs and the delicate larvcB which, swimming at or near the 
surface, are suffocated by the deposit of an impervious film on the 
gill surface; by destroying the minute surface plants and animals on 
which these larviB and some of the adult fishes subsist; by diminish- 
mg the aeration of the water at the surface and thereby aggravating 
the deoxidizing eft'ects of organic pollutions from municipal sewage 
and similar sources: l)y destroying spawning grounds; by killing the 



OIL AND TAB. POLLUTION OF WATERS. 5 

shallow water vegetation which directly or indirectly furnishes fish 
food and shelter; and by impairment of the market value of fish 
through imparting to them an offensive taste. 

DIRECT TOXIC EFFECTS. 

A great variety of tars and tar oils, either from coal or petroleum, 
have been shown to be highly poisonous. Butterfield and writers 
in the (London) Fishing Gazette and the Salmon and Trout Maga- 
zine, and Shelford and Thomas in this country (see bibliography) 
have reported various experiments which show that tar and tar 
oils are poisonous in great dilutions. Tars or tar oils result from 
distillations of coal, petroleum, woods, etc. These distillation 
products are very complex and varying in composition, but all may 
be assumed to contain some of the substances which, in very weak 
dilutions, have been shown to be highly poisonous to various fishes. 
Phenols and cresols (in dilutions of less than 100 parts per million) 
have been found quickly fatal by Butterfield and Shelford. Other 
constituents which are quickly fatal in the dilutions indicated are 
phenanthene and naphthalene (4 to 5 parts per million) ; xylene, 
toluene, benzene, and ethylene (22 to 65 parts per million); sulphur 
compounds, as hydrogen sulphide (5 parts per million), sulphur 
dioxide (16 parts per million) ; carbon bisulphide (100 parts per 
million) ; thiophene (27 parts per million) ; ammonia (7 parts per 
million) ; and ammonium salts and other nitrogenized compounds 
(some hundred parts per million) ; quinoline and isoquinoline (50 to 
65 parts per million). The strengths given as quickly fatal are those 
which have caused death in one hour, or very little more, to sunfish 
(American) or gudgeon (European) , fish which seem more than ordi- 
narily resistant to poisons. It is stated (Seydel) that Russian 
investigators find hexahydrobenzoic acid (C^HnCCCH), to be the 
essential poison of Russian petroleum, and that 4 to 16 parts per 
million were quickly fatal to a cyprinid and a percid. 

The experiments of Thomas and others indicate that prolonged 
exposm'e to very much greater dilutions of these substances are 
fatal. Dilutions of various tars and crude distillates of petroleum, 
which required 66 or more parts per million for quick fatality, have 
proved fatal in strengths of from 13 to 33 parts per million in from 
1 to 3 days. A great variety at 13 parts per million proved fatal in 
3 days. One liquid tar waste at 2 parts per million killed sunfish 
{Lepomis Jiumilis) in one day. 

MECHANICAL EFFECTS. 

Certain petroleum products appear to contain no poisonous sub- 
stances soluble in water and to have little direct effect when allowed 
to form a surface film, but when emulsified by agitation prove deadly. 
A high-boiling petroleum distillate and a light fuel oil were found by 
Thomas to be quite harmless, unless as aeration retarders, or unless 
emulsified, as by continued moderate agitation, when the}^ coated 
the gill membranes of the fish and caused death by suffocation. 
Rushton found that by shaking up 1 part of beazinc with 40,000 parts 
of water, a mixture was formed which killed fish in five minutes^ 
apparently entirely from poisonous action. 

68637*'— 21 2 



6 U. S. BUREAU OF FISHERIES. 

Doubtless under the agitjition of continued wave action many, if 
not all, oils and oily substances will emulsify or mix to a considerable 
extent and so coat the gills of fish or other forms, or have a poisonous 
effect which their insolubility would otherwise prevent. According 
to Weigelt, ulcerations and attacks of disease have been found to 
follow the irritating action of petroleum products. 

The eggs of sea hslies which do not seek fresh, brackish, or shore 
waters in which to spawn differ from the eggs of all these and of 
fresh-water species in that they are typically floating. In many 
cases, at least, the larvse for a time are also floating. This fact ren- 
ders the possibility of grave danger to the great sea fisheries a very 
striking one, for it can scarcely be thought that eggs can hatch and 
young normally develop in a medium of oil. The eggs and larvae 
of oysters and other shellfish are not surface floating, but arc carried 
up and down by the current, sometimes to the surface. A special 
danger to them lies in the fact that both oil and larvre (and eggs) 
are prortc to collect in eddies. 

TREVENTION OF AERATION OF THE WATER. 

The question of aeration prevention by an oil film is a very impor- 
tant one. Butterfield and Thomas have questioned considerable 
prevention, Butterfield on the supposition that mineral oil is similar 
to water in its oxygen absorption, and Thomas apparently on the 
theory that incomplete rather than complete films tend to form. 
There need be no question that extensive films do form. Further- 
more it seems established by Adeney, especially in stilt water and 
any water of considerable mineral content, that streaming, with the 
consequent distribution of the air saturated surface water, is largely 
dependent upon evaporation and increased density at the surface. 
If this is the case it must follow that an oil film, by preventing 
evaporation, greatly checks aeration. Danger from this seems 
cliiefly to center m harbors where, because of general pollution, 
particularly sewage pollution, the oxygen consumption is greatest and 
wliere, because of ^as plants and sliipping and the great number of 
automobiles, the discharge of oil is also extreme. These are the 
same harbors which are the gateways to the great natural spawning 
areas of the anadromous fishes. 

In connection with the prevention of aeration, oxygen loss by the 
absorption of dissolved oxygen, by fatty acids and other substances 
present in oils and tars, should be taken into consideration. 

DESTRUCTION OF FISH FOOD. 

Indirect action of oils and tars may consist of poisonous action on 
food organisms. Prawns appear very susceptible to tar poisons, and 
in English streams it has appeared that tarred road washings are 
even more destructive of insect life than of trout directly. It can 
scarcely be doubted that the susceptibility of minute forms is at 
least of the same order as that of lish. With a number of micro- 
scopic forms, particularly diatoms, it is known that their suscepti- 
bility to a number of poisons is greater than that of fish (Whipple, 
Moore, and Kellerman). Destruction ma}', of course, be secondary, 



OIL AND TAR POLLUTION OF WATEES. 7 

as from lack of oxygen, or from the destruction or spoiling of emergent 
or littoral vegetation with an oil coating, particularly in tidal areas 
(by which means wild fowls may also greatly suffer) , and the conse- 
quent loss of a productive habitat. 

From gas houses, tarred roads, and refineries much of the contam- 
ination eventually finds its way to the bottom to render it more or 
less sterile according to thickness and completeness of the deposit 
and the constancy with which the deposit is maintained. Wadham 
indicates that he found apparently complete strata for each fresh 
tarring of road, and that it took two or more years for a trout brook 
to recover proper productivity of fish. 

In some waters the basic fish food consists in part of air-breathing 
larvae and pupae of insects, which, if a layer of oil is present, as is well 
known, will be unable to come to the surface to breathe and so will 
be destroyed. Young of food fishes or the small fish on which food 
fishes feed will in consequence be deprived of an important source 
of food, and the productivity of the region will be correspondingly 
decreased. In 1920, through the Gulf States, Mr. Hildebrand found 
that Gambusia and Fundulus, which feed largely on such larvse and 
pupae, disappeared from oil-covered water. He took no special notes 
in regard to larger species, but believed they disappeared also, pre- 
sumably because their food had disappeared. 

SUMMARY. 

Three main sources of oil and tar pollution have been found : Road 
washings, carrying great quantities of lubricating oil; ^as houses and 
oil refineries; tankers, oil burners, and oil-engined shipping. Tars, 
tar oils, and crude distillery products are found generally to be highly 
poisonous, whether in weak or great dilution. Some oils have been 
found to emulsify to a sufficient degree, with continued agitation, 
to coat the gills of fish and so produce death by sufl'ocation. An oil 
film, through prevention or checking of aeration, is dangerous, par- 
ticularly in busy harbors. The deleterious effect on spawning, by 
rendering spawning grounds unfit or inaccessible, is a grave danger 
arising from the pollution of harbors and streams. Another serious 
danger is found to lie in the possible effects on the diminution of the 
food supply. Through whatever means, it is an observed fact, 
according to Weigelt, that in Germany fish have completely disap- 
peared from pools and ponds following the discharge of mineral oil 
into the water. In the sea a great danger is suggested by the fact 
that the eggs of sea fishes are typically floating, and that oil-burning 
and oil-engined shipping is greatly increasing. 

Remedial measures may (now or in the future) be found: (1) In 
the recovery of oils from drainage water, as already has been pro- 
posed; (2) in the prevention of gas-house and refinery pollution, 
which prevention should be helped by the increased use of "wastes" 
in by-products; and (3) in prevention, by international arrange- 
ments, of the dumping of oil from ships in harbors or in the region of 
spawning grounds or special feeding areas. 



BIBLIOGRAPHY. 

Adeney, W. E. 

1912. Report of W. E. Adeney. In Present sanitary condition of New York 

harbor and the degree of cleanness which is necessary and sufficient for 

the water. Report of the Metropolitan Sewerage Commission of New 

York, 1912, p. 80-121. Wynkoop Hall«nbeck Crawford Co., New York. 

Allen, E. J. 

1914. Letter telling of deadly effects on swimming prawn of creosote oil in great 
dilutions. In Net curing bv creosote. Fish Trades Gazette, Vol. 31, 
Feb. 28, 1914, p. 36. London. 

BUTTERFIELD, W. T. A. 

1912. The relation of modern road sm-facing to iish life. The Survevor. Vol. 
41, Feb. 16, 1912, p. 277-284. London. 

COKER, R. E. 

1920. Progress in biological inquiries. Ke])ort of the Division of Scientific 

Inquiry for the fiscal year 1920. Appendix II, Report, U. S. Com- 
missioner of Fisheries for 1920. Bureau of Fisheries Doc. No. 896. 
p. 23. Washington. 
CoLLiNGE, Walter E. 

1921. The effects of oil from shii)s on certain sea birds. Nature, Vol. 106, Feb. 

24, 1921, p. 830. London. 
Fishing Gazette (The). London. 

1910. Note by editor, R. B. Marston, containing letter from R. C. W. H. Butler 

telling of harmless leakage of a barrel of crude tar into trout ponds. 

The Fishing Gazette. Vol. LX, June 4, 1910, p. 508. 
■Note by editor quoting letter from Arthur J. Belcher (extracted from the 

Daily Mail of June 14) telling of the immediate destruction of hundreds 

of trout followdna; the washing of tar from a freshly tarred road into 

trout brook. Ibul., Vol. LX, June 18, 1910, p. 559! 
Letter from A. Pi.. Peart telling of experiments showing deadliness to 

fish life of water which has been in contact with fresh crude tar; also 

pointing out that road washings may be expected to reach stream while 

it is still shrunken by preceding drought. Ibid., Vol. LX, June 25, 

p. 607. 
Account by Field of destruction of lisli and vegetation following tarring 

of roads, and of finding a high tar content in road washings. Ibid.. 

Vol. LXI, July 23, 1910, p. 99-100. 
Letter (anon.) telling of experiments showing deadliness to trout at various 

dilutions of water which had been in contact with coal tar. Ibid., Vol. 

LXI, July 30, 1910, p. 12^126. 
Note by editor containing letter from '"Elfa" telling of development of 

fungoid growth follo^ving the washing of tar from road into stream. 

Ibid., Vol. LXI, Aug. 6, 1910, p. 144. 
Note by editor quoting note from Percv Wadliara on the road-tarring 

question. Ibid., Vol. LXI, Aug. 20, 1910, p. ISS. 
Investigation of an epidemic of fish jxnsoning by tar at Drinkwater Park, 

Manchester, by E. J. Sidebothani and A. Sellers. {From Archives 

of the Public Health Laboratoiv of the Universitv of Manchester, Vol. I, 

1906.) l])id.. Vol. LXI, Aug. 27, 1910, pp. 210-211. 

1911. Note by editor quoting account from Dundee Courier of Aug. 5, 1911, of 

the washing by thunder storm of tar from freshly tarred road in the 
River Faiy, the killing of many scores of fine trout, and the ruining of 
the fishing below. Ibid., Vol. LXIII, Aug. 12, 1911, p. 163. 
Letter from F. I. C, one technically informed, telling of amounts of 
naphthaline and phenol I)odies allowed in road tar and maintaining 
that treatment which renders tar innocuous spoils it for road work. 
Ibid., Vol. LXIII, Aug. 26, lOl!, p. 233. 

8 



OIL AXI) TAR rOLLUTlOX OF WATKRS. 9 

1912. Note by editor quoting letter from S. Jafte telling of destruction of fush 

and small and microscopic forms by leakage of 2,200 cubic yards of lar 
and by-products and of over £1,600 paid in damages; and letter from Karl 
Heintz to the effect that it is illegal in Bavaria (or all Germany?) to 
construct drains from tarred roads into streams. Ibid., Vol. LXV, 
Dec. 21, 1912, p. 582. 

1913. Note by editor quoting extract from Isle of Wight < 'ountv Press telling of 

settling with F. T. Mew, of Carrisbrooke, Isle of Wight, for £325 for 
damage to fishery by tarred-road washings. Ibid., Vol. LXVI, Mar. 15, 
1913, p. 66. 
Letter from Percy Wadham on the difficulty of determining the real 
danger from tar poisonina: by laboratory experimentation. Ibid., Vol. 
LXVI, May 24. 1913, p. 480." 

1914. Note by editor quoting letter from F. Napier Sutton on the effect of leak- 

age from gas works on a fishery. Ibid., Vol. LXVIII, Jan. 3, 1914, p. 2. 

1917. Note by editor quoting letter from Percy Wadham telling of lasting poison- 
ousness of tar on roads and of formation of tarry strata on pond l)ottoms, 
etc. Ibid., Vol. LXXIV, Feb. 24, ]9]7, p. 100. 

1921. Report of adcb'ess by J. A. Simpson delivered at Nottingham Januaiy 12 
before '"An Alliance for Prevention of lliver Pollution," telling of 
fining of Derbyshire County Council and of damages obtained by riparian 
owiiers for destrnction of fishing by tarred -road washings. I]>id., Vol. 
LXXXII, Jan. 22, 1921, p. 45. 
Note by editor to the effect that the Joint <'ommittee of Ministry of Agri- 
culture and Fisheries and the Ministry of Transport have been unable 
to find a safe tar; refers to an account by Dr. Smith, U. S. Commis- 
.siouer Fisheries, of experiments to find a safe tar with out success. Ibid., 
Vol. LXXXII, Feb. 26, 1921, p. 117. 
Forbes, S. A. 

1894. Kepoi I ou effect of oil-well and gas-house waste on fish and fisheries of the 
\\'a!ju,.ih Ki\er. In House of Representatives Miscellaneous Document 
No. 196, 53d Congress, 2d Session, p. 2-5. Also quoted by Richard 
Rathbun in Report of Commissioner, U. S. Commission of Fish and 
Fisheries for 1894 (1896), p. 109-112. Washington. 

HlLDEBRAND, SaMUEL F. 

192 L Top minnows in relation to malaria control, with notes on their habits and 
distribution. Public Health Bulletin No. 114, U. S. Public Health 
Service, Treasury Department, p. 17. Washington. 
Home, David Milne 

1883. Salmon and salmon fisheries. International fisheries exhibition. Lon- 
don, 1883. Conference on July 17, 1883. The Fisheries Exhibition 
Literature, Vol. VI, Conferences, Part III, 58 p. William Clones and 
Sons, Limited. Loudon. 
Lenzing, C. W. 

1917. Effect of gas-house waste on the biochemical oxydation of sewage. Uni- 
versity of Illinois Bulletin, Vol. 15, No. 11, Water Sui'vey Series No. 15, 
( hemical and Biological Survey of the A\'aters of Illinois, Report for . . . 
1916, p. 168-174. l]rl)ana. 
McDonald, Makshall 

1885. Report on the pollution of the Potomac River l)y the discharge of waste 
products from gas manufacture. Bulletin, U. S. Fish Commission, 
Vol. V, 1885, p. 125-126. Washington. 
Effect of waste products from Page's ammoniacal works upon young shad 
fry. Ibid., p. 313-314. 
Marsh, Millaijd Caleb 

1907. The effect of some industrial wastes on fishes. {Reprint from The Potomac 
River Basin, U. S. Geological Survey, Water Supph' and Irrigation 
Paper No. 192, p. 337-348.)' U. S. Fisheries Doc. No. 619. Washington. 
Moore, George T., and Karl F. Kellerman 

1905. (Copper as an algicide and disinfectant in water supplies. Bulletin 76, 
Bureau of Plant Industry, U. S. Department of Agriculture, 55 p. 
Washington. 
Mosely, Martin E. 

1920. Trout fishing and road tarring. Salmon and Trout Magazine, No. 21, 
March 1920, p. 70-73. London. 



10 U. S. BUEEAU or FISHERIES. 

Richmond, F. G. F' 

1914. Some questions of tar. Salmon and Trout Magazine, No. 9, December^ 
1914, p. 35-42. London. 

RUSHTON, W. 

1921. Biological notes. Salmon and Trout Magazine, No. 25, .\pril, 1921, p. 114. 
London. 
Salmon and Trout Magazine. London. 

1916. Road tarring. Salmon and Trout Magazine, No. 14, October, 1916, in 

Editorial Notes, p. 6-7. 

1919. The road-tarring question. Ibid., No. 18, April, 1919, p. 51-57. 
Road tarring. Ibid., No. 20, November, 1919, in Editorial Notes, p. 7. 

1920. Road tarring and fisheries. — Work of the Joint Committee. Ibid., No. 23, 

September. 1920, in Editorial Notes, p. 9-10. 
Scientific American. 

1921. Wlien oil stops the shifting sands. Scientilic American, Vol. CXXV, 

No. 5, July 30, 1921, p. 83. Munn & Co., New York. 

Seydel, E. .. 

1914. tjber die Wirkung von Mineralolen auf Fischwasser. Mitteilungen des 
Fischereivereins, f. d. Provinz Brandenburg, Bd. 5, p. 26-28. Re- 
viewed in Wasser IT. Abwasser, Bd. 7, p. 49. 

Shelpord, Victor E. 

1917. An experimental study of the effects of gas waste upon fishes, with especial 

reference to stream pollution. Bulletin, Illinois State Laboratorv of 
Natural History, Vol. XI, Art. VI, p. 381-412. Urbana. 
Shipley, A. E. • 

1921. Oil from ships. Effects of discharge in the sea. Suffering iisheries. 
Letter to the editor, London Times, January 21, 1921, p. 6. 
Thomas, Adrian. 

. A study of the effects of certain oils, tars, and creosotes upon brook trout 

(Salvelinih'; fontinalis) . Manuscript. 
TowNSEND, Charles H. 

1908. Pollution of streams — an appeal to anglers. Reprinted from the twelfth 
annual report of the New York Zoological Society, 1908, 7 p. New York. 
Ward, Henry B. 

1919. Stream pollution in New York State. A preliminary investigation of the 
problem from the standpoint of the biologist. Made in July and August, 
1918. State of New Yorlc Conservation Commission, Albany. J. B. 
Lyon & Co., Printers. 
Weigelt, C. 

1904. L'assainissement et le rapeuplement des rivieres. Traduction fran^aise 
de C. Julin. (Extrait du tome LXIV, M^moires couronnes et autres 
M6moires, publics par I'Acad^mie royale de Belgique, 1903.) 668 p. 
Carl Heymanns Verlag, Berlin. 
Whipple, George Chandler. 

1914. The microscopy of drinking water. 409 p. John Wiley & Sons, Inc., 
New York. 
Wilson, H. Maclean and H. T. Calvert. 

1913. A text-book on trade waste waters: their nature and disposal. XII, 340 p. 
C. Griffin & Co., Limited, London. 

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